The Borg were great when they were mysterious and unfathomable, when they only appearances were in Q Who and Best of Both Worlds. After BoBW, the Borg were milked and became less intimidating, mysterious, and creepy with each appearance. They were a total joke in First Contact and Voyager.
Don't milk things. Stop. Let things be one and done.
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Also, for those who don't know, the parasite aliens at the end of S1 were supposed to be the Borg, but the stop-motion aliens were too expensive from a budget standpoint to do a repeat appearance, so the Borg were retconned/recontextualized into being humans with grey paint and prosthetics attached.
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Another fact: for those who complained that Picard's ultra-violent behavior in First Contact was out of character. Well, yes, he was OOC compared to the rest of the show... but
in the season 1 finale, he murdered a Borg without remorse (remember, the aliens were supposed to be Borg but were too expensive). So... consistency!